The question is what kind of effect they have on the audience. If someone uses exclusionary language in front of a diverse community that can be really destructive.
Something else to consider though, the amount of contempt for ones views that may be unpopular, for me is contrary to a diverse community, in fact disinviting people is exactly the opposite of being inclusive. I’m unsure how you can have a diverse community without having people who aren’t always inclusive, by trying to weed them out you inherently become what you lament. No?
That excuse just does not work. Who are these fragile people who would be destroyed by Bob Martin's thoughts on programming? And why are they more important than all the other people who would want to listen to a guy that has been successfully writing software longer than almost anyone still working?